Grain-drier



(No Model.)

L. BORLAND.

GRAIN DRIER.

No. 403,412. Patented May 14, 1889.

UNITED STATES PATENT" OFFICE.

LENVIS BORLAND, OF SAN FRANCISCO, CALIFORNIA.

GRAIN- DRIER.

SPECIFICATION forming part of Letters Patent No. 403,412, dated May 14, 1889.

Application filed October 1, 1888.

To all whom it may concern.-

Be it known that I, LEwIs BORLAND, of the city and county of San Francisco, State of California, have invented an Improvement in Grain-Driers; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to that class of graindriers in which the body of grain passes down between the perforated walls of a vertical column or passage, through which, from side to side, the heated air is passed; and my invention consists in the construction and combination of devices, which I shall hereinafter fully describe and claim.

The object of my invention is to provide for subjecting the grain at the beginning and end of the operation to a high degree of heat, and at the middle of the operation to a lower degree.

Referring to the accompanying drawings for a more complete explanation of my invention, Figure 1 is a vertical cross-section of my drier. Fig. 2 is avertical section of the chimney or outlet. Fig. 3 1s a view of one of the stirrers.

A is the'shell of the furnace, having within it at its base the separate fire-chambers B. Within the shell are the grain-passages O and D. These are vertical and are formed by side walls, 0 and (Z, which are made of wire-netting, screen material, or other perforated plates. These passages are separated by a small space, so that each is wholly independent of the other. The passage 0 has communicating with its top the main feed-hopper E.

F is an endless elevator, the lower end of which is in communication by means of a spout, G, with the lower end of the grain-passage O, and the upper end of the elevator communicates by a spout, H, with the upper end of the vertical grain-passage D. The lower end of graimpassage D communicates with a suitable discharge.

The shell is here shown as divided into an upper portion and a lower portion by the arches at a. The space below these arches forms the lower drying chamber, a, said chamber communicating on the left-hand side with one of the fire-chambers below and on the right-hand side with the flue I of the chimney J, Fig. 2. Above the divisional arches a Serial No. 286,900. (No model.)

the space about the grain-passages forms an upper drying-chamber, a which communicates on the right hand with the other firechamber and on the left with the flue I of the chimney J, Fig. 2. The hot air and products of combustion from the fire-chamber on the left pass upwardly into the lower drying-chamber, a, thence to the right, traversing the grain-passages D and O and the body of grain contained therein to the other side of the chamber, and thence out through the chimney. The hot air and products of combustion from the other fire-chamber pass up wardly to the upper dryingchamber, a and thence to the left, traversing the grain-passages C and D and body of grain therein to the other side of the said drying-chamber, and thence escape through the chimney. The course of the heated gases, &c., is shown by the arrows.

Now, it will be seen that the temperature of the grain in that passage which the heat first strikes will be higher than the temperature of the grain in the adjacent passage. For example, in the lower portion of the passage D the temperature may be 270, while the temperature in the lower portion of the passage 0 will be as low as 180, it being borne in mind that although the passages are not very far apart the heat must pass through a large body of grain before it can reach the second passage, and therefore much of it is absorbed, and the temperature in the second passage is considerably reduced. Likewise in the upper drying-chamber the passage 0 maybe 250 in point of temperature, while the passage D will be 140. The effect of this in operation will now be seen.

I have found it advisable to give the grain at the beginning and end of the operation a very high heat and at the middle a lower degree. This is gained by feeding the grain from the hopper E into the passage 0, the upper portion of which is very hot. As it passes down in the passage 0, the temperature is gradually lowered, and is perceptibly reduced in the lower portion of said passage. The grain then passes from the passage 0 through the spout G to the elevator, and is by it carried upwardly and discharged through the spout H into the upper end of the passage D,

in which portion of said passage it is still subjected to a low degree of heat; but as it passes down the passage and nears the end of the operation it is subjected once more to a high degree of heat before passing to the discharge.

Within the passages O and D at any suitable points are the stirrers N. These are shown in Fig. 3, and consist of a central shaft with arms or heads, between which extend the peripheral bars or blades n. These stirrers are mounted and adapted to rotate in the passage, power being imparted to them by suitable gears and connecting machinery unnecessary herein to show. The diameter of the stirrers is a little less than that of the width of the passages, so that as the blades n rotate they come in close proximity to the walls of the passages, and thereby remove the grain from said walls, which would without stirring pass down the whole length in contact therewith; but with the stirrers the body of grain is mixed up, so that specific grains will not be in the same position, thereby providing for a more uniform heat. The discharge of the grain into and from the elevator also tends to this resultthat is to say, mixing it up, so as to subject it more uniformly to the action of the heat.

an exhaust-opening communicating with its I other side, and an elevator or conveyer conimunicatin g with the lower end of the passage which is cooler at its bottom than at its top and with the upper end of the other passage, substantially as herein described.

In Witness whereof I have hereunto set my hand.

LEWIS B ORLAND.

Witnesses:

.S. H. NOURSE,

H. 0. LEE. 

